Multifilter assembly for filtering oil or liquids



June 14, 1949.

c. c. s. LE CLAIR MULTIFILTER ASSEMBLY FCR FILTERING OIL OR LIQUIDS'Fild March 15; 1945 5 Sheets-Sheet l Inventor:

TZ/LJJ? M A ttorneys June 14, 1949. c. c. 5. LE CLAIR MULTIFILTERASSEMBLY FOR FILTERING OIL OR LIQUIDS Filed March 15, 1945 5Sheets-Sheet 2 Ipvenlor viz-w a [2417" y Aadliuzk 9 Ailormzy:

June 14, 1949. c. c. 5. LE CLAIR 2,473,032

MULTIFILTER ASSEMBLY FOR FILTERING OIL OR LIQUIDS Filed March 15, 1945 5Sheiets-Sheet s Attorney-s MULTIFILTER ASSEMBLY FOR FILTERING OIL 0RLIQUIDS Filed March 15, 1945 June 14, 1949. c. c. 5. LE CLAIR 5Sheets-Sheet 4 Attorneys FIGS.

June 14, 1949. c. c. 5. LE CLAIR 2,473,032

MUL'I'IFILTER ASSEMBLY FOR FILTERING OIL O R LIQUIDS Filed March 15,1945 5 Sheets-Sheet 5 In ventor:

/ Attorney 6.

Patented June 14, 1949 MULTIFILTER ASSEMBLY FOR FILTERIN OIL OR LIQUIDSCamille Clare Sprankling Le Clair, Acton, London,

England, assignor to Tecalemit Limited, Brentford, England, acorporation of Great Britain Application March 15, 1945, Serial No.582,883 In Great Britain February 17, 1944 3 Claims. (Cl. 210-168) Thisinvention relates to duplex filter apparatus, for use in filtering orcleaning oil or liquid, of the type in which each filter unit comprisesa filter element contained within a container which is detachablyattached to a head provided with inlet and outlet connections.

Where filter apparatus is fitted in an oil or liquid system designed forcontinuous operation over long periods, it becomes necessary to providemeans whereby soiled filtering elements may be removed and replaced byclean ones while the apparatus of which it forms a part is still inoperation.

To accomplish this it is known to fit two or more filters in paralleland to connect them'up with control valves in such a way that any one ormore may be isolated from the system for cleaning while the othersremain in operation.

In practice it is not usual to fit more than two filters but even withonly two filters the operations necessary to change over from one filterto the other are not simple and it is essential that they should beperformed in their correct sequence because otherwise accidents ordefective performance might occur. For instance, assuming that onefilter is in use and the other filter is standing ready to be put intooperation, it is necessary: to open the inlet to the filter not in use;toopen the outlet from that filter; to close the inlet to the filter inuse; to close the outlet from the filter in use; to remove the containerand the used filter element from the filter previously in use; to cleanout and fit a new filter element; to replace and secure the container inposition and to prime the filter which is now empty, for which purposeit is necessary to vent the air entrapped to atmosphere so that it doesnot get into the oil or liquid system and thus cause trouble.

One object of the present invention therefore is to provide meanswhereby the above operations may be simplified, a second object being toprovide locking means whereby it becomes impossible to openinadvertently any filter or filters which is or are in the workingcircuit.

For simplicity, oil and liquid will be referred to hereinafter asliquid.

One constructional formof the invention is shown, by way of example, onthe accompanying drawings, whereon:

Fig. 1 is an elevation, partly in section of the filter assembly;

Fig. 2 is a plan view:- I

Fig. 3 is a section on the line x-x in Fig. 2;

Fig. 41s a plan view of the underside of the valve cover;

Fig. 5 is a plan view of the control valve;

Fig. 6 is a plan view of the valve plate;

Fig. 7 is a plan view of the underside of the valve plate;

Fig. 8 is a plan view of the carrier;

Fig. 9 is a plan view of the underside of the carrier;

Fig. 10 is a fragmentary plan'view of the valve cover and shows thelocking plate; and

Fig. 11 is a fragmentary enlarged view of th control valve operatinghandle.

Referring to the drawings:

This filter assembly comprises two spaced filters which, for the purposeof description, will be called filter A and filter B. The duplex filterincludes a common head which, for manufacturing reasons, is built up ofthree castings, namely a carrier I, a valve cover 2 and a valve plate 3between the carrier and cover, these 'parts being bolted together.Pressure-tight joints are formed between the adjacent faces of thecarrier and the valve plate and between the adjacent faces of the valveplate and the valve cover by means of gaskets. The carrier is adapted tosupport two filter container bodies 4 and 4A of equal capacity, each ofwhich is attached to the common head by means of a central holding bolt5, the bottom end of which is screwed into a boss 6 projecting upwardlyfrom the bottom of the container body. Hand knobs 1 are attached to thetop end of the bolts 5 and bear against the top of the valve cover 2when the bolts are tightened up. Pressure-tight Joints are formedbetween the top edges of the container body and the carrier l by meansof joint washers 8 fitted in spaced annular recesses formed in thebottom face of the carrier l. Flter elements 9 of known construction(for instance, of the fabric type) are arranged in the container bodiesbetween top pressure plates I0, fitted on hollow bosses l l whichproject downwardly from thecarrier i, into thecontainerbodies and thefilter elements, and bottom pressure plates l2 which are pressedupwardly by springs l 2A. The

bosses I I are bored to'form oil outlet ports l3, see

Figs. 1, 8 and' 9, surrounding the bolts 5 from the interior of therespective filter elements 9. The

holding bolts 5 pass upwardly through holes l4 and MA in thevalve'plate, see Figs. 6 and '7, and

also through hollow bosses I5 and 15A projecting downwardly from thevalve cover 2. The carrier I is also formed with two spaced ports l6 andll, of which the port l6 forms an oil inlet which com municates with theannular space l8, Fig. 1, be-

tween the filter element and container body of filter B, while the otherport i1 forms an oil inlet which communicates with the equivalentannular space (not shown) between the filter element and container bodyof filter A.

The upper or valve cover part 2 of the head forms a chest and a coverfor a disc type control valve l9, Figs. 3 and 5, which will be describedhereinafter. The valve cover is formed with an oil inlet connectionwhich communicates with a large oil main inlet chamber 2| formed in thecover and surrounding the boss |5A, through which the holding bolt 5 offilter B is passed, and a central boss 22 which will be referred tohereinafter. Spaced from the said main inlet chamber 2| an arcuate oiloutlet passage 23 is also formed in the valve cover and communicateswith a main oil outlet connection v24 leading from the cover. Betweenthe main outlet connection and the main inlet chamber there is a hole 25in a boss I5 through which the holding bolt 5 of the filter A passes. Asmentioned above, the valve cover 2 is superimposed upon the valve plate3. The lat ter is formed on its upper surface with a shallow circularboss 25 which registers with the circular wall 25A of the main inletchamber 2| in the valve cover, Figs. 3, 4 and 6. The top surface of theboss 25 is machined to form a fiat valve face. Referring to Figs. 6 and7, as viewed in plan, the boss 25 may be considered to be divided intoseven equal sectors, and it is formed with a set of three adjacentsector-shaped outlet ports 21, 28 and 29, each occupying one sector, anda set of two adjacent sector-shaped inlet ports 35 and 3|, each alsooccupying one sector, the two remaining sectors being left blank orunperforatecl. The outlet port 21 is adapted to communicate with the oiloutlet i3 from filter A, the centralport 25 of the set is adapted tocommunicate with the outlet passage 23 and the main outlet connection 24from the valve cover 2, and the other port 29 is adapted to communicatewith the oil outlet l3 from filter B. These ports are arranged alongsideone another and are separated by ribs. The inlet port 30 is. adapted tocommunicate with the said oil inlet IT to filter A and the other inletport 3| is adapted to communicate with the oil inlet Hi to filter B.These two inlet ports are also separated by a rib. The set of threeoutlet ports is separated from the set of two inlet ports by the twoblank or unperforated sectors of the valve face, one sector being oneither side. The inlet port in the valve face communicates with the oilinlet port H to the filter A through a passage 33 formed in theunderside of the valve plate 3. The inlet port 3| in the valve facecommunicates with the inlet port l5 to filter B through a similarpassage 34 formed in the underside of the valve plate 3. Similarly, theoutlet ports 21 and 29 in the valve face 25 communicate, respectively,with the outlets |3 from filter A and filter B via the passages 35 and35 formed in the underside of the valve plate. The central or mainoutlet port 28 in the valve face 25 communicates with a peripheralpassage 31 in the underside of the valve plate 3 which surrounds theaforesaid passages and is substantially of oval formation. This mainoutlet or peripheral passage 31 communicates at one end with an arcuateport 38 which registers with the aforesaid arcuate passage 23 in thevalve cover 2 and,

4 separated from each other by ribs as shown in Fig. '7.

Referring to Fig. 5, the disc type control valve I9 is circular and, asshown in Fig. 3, is formed with a flat face 39 which is turnably mountedupon the valve face 25 of the valve plate 3. Like the valve face, thecontrol valve may be considered to be divided into seven sectors, ofwhich one 40 is left blank or unperforated and is flanked on one side bya sector-shaped inlet port 4| which is adapted to communicate with theinlet l1 to the filter A through the inlet port 35 and the passage 33 inthe valve plate. On its opposite side. the blank sector is flanked byanother sectorshaped inlet port 42, which is adapted to communicate withthe inlet I5 to the filter B through the inlet port 3| and the passage34 in the valve plate. Two of the other remaining four sectors of thecontrol valve are apertured, connected, and enclosed by a housing 43 soas to form a transfer passage 44, which is flanked by, and is separatedfrom, the said inlet ports by two further blank or unperforated sectors45 and 45, one on either side.

Means are provided for turning the control valve through an angle ofabout 51, i. e., through one of the aforesaid sectors. These meanscomprise a key having a spindle part 41, Fig. 3, which is turnablyarranged in a hole 41A formed in the central boss 22 in the valve cover2. The spindle part 41 of the key is integral with a flange 48 in whichare formed two holes (not shown) into which two driving pins 49, Fig. 5,projecting upwards from the control valve i9, engage. A coil spring 50housed in a recess 5| in the control valve reacts between the latter andthe flange 48 of the key and thus acts to press the valve down upon itsvalve face 25 and also to press the flange into pressure-tight contactwith a sealing washer 52 surrounding the spindle part of the key in theboss 22 in the valve cover 2.

The control valve is actuated by means of a hand lever 53 formed with acircular enlargement or heel at its inner end which, as shown in Figs.10 and 11, is provided with a T-shaped opening 54, the metal of the stempart of which is turned upwards to form a lug 55. The upper end 413 ofthe spindle part 41 of the key is flatted on two sides leaving a tonguelike projection which engages in the cross part of the T-shaped openingformed in the heel of the hand lever 53 which heel is turnably arrangedon the outside of the valve cover 2 upon a sealing washer 51 and in arecess formed in a sliding bolt plate and cover plate about to bedescribed. The hand lever is secured in position laterally by itsengagement with the top end of the spindle as explained above.

Immediately above the heel of the hand lever 53 a bolt plate 50, seeparticularly Fig. 10, is slidably mounted. The bolt plate comprises acentral part 5| and two lugs 52 and 53 projecting from its oppositeends. A T-shaped aperture 54, see also Fig. 11, through which the topend of the key-spindle 41 projects is cut centrally in the central part.The cross part of the T lies longitudinally of the bolt and issufllciently long to permit the bolt to move through its designed strokewithout fouling the spindle, while the stem part 55 of the T liestransversely of the bolt and engages the lug 55 of the hand lever. Thebolt plate 5| is held in position and guided by a cover plate 55 whichis fixed to the valve cover 2 by screws 51 arranged on opposite sides ofthe bolt plate clear of the circular heel of the hand lever. At itsfront end, the hand lever 53 is formed with a 5 curved actuating handlepart "A which cooperates with two spaced stops 63 and 39 on the valvecover designed to limit the range of the turning movement of the handlever 33 and, thereby, that of the control valve I9 to the aforesaid 51approximately. The lug 62 on the bolt plate is adapted to engage in anyone of a series of spaced recesses 10 formed in a flange 'II integralwith the hand knob I attached to the holding bolt 5 of the filter A andthe lug 63 on the bolt plate is adapted to engage in any one of a seriesof spaced recesses I2 formed in a flange I3 integral with the hand knobI attached to the holding bolt 3 of the filter B.

The purpose of the bolt plate 30 is to prevent either filter beingopened when in operation. Thus, when the hand lever 53 is turned to theleft as shown in Figs. 2, 10 and 11, the bolt plate is moved to theright by the engagement of the lug 36 with the slot 35, and the lug33engages in one of the recesses I2 in the flange 13, thereby preventingthe filter B being opened. If the hand lever is moved to the right, thebolt plate 60 is moved to the left and the lug 62 is engaged in one ofthe recesses I in the flange II, thereby preventing the filter A beingopened.

Figs. 3 and 9 illustrate the means for priming the filters. These meanscomprise a priming valve having a fiat valve face I4 .of rubber or likematerial attached to a flange "I5 provided with a stem I6 of metal orplastic material. The valve is slidably arranged in a hole formed in aboss I1 projecting forwards from the carrier I between the two containerbodies 4 and 4A. This hole is closed by a hollow valve cover I8 which isscrewed into the hole and is formed with a hole through which the valvestem I6 is slidable. The stem projects out of the cover and its outerend is attached to a hollow knurled knob I9 whereby the valve may bepulled off its port face "A in opposition to a spring 80 which reactsbetween the cover and the flange I5 of the valve. The said port face isconnected by two spaced right angled ports 8| and 82 to the two passages33 and M, Fig. 7, in the underside of the valve plate 3, whichcommunicate respectively with the liquid system at the inlets I I and Itto the filters A and B.

Any air entrapped in the two filters A and B can be vented therefrom bymeans of two vent valves 84, Fig. 1, which allow air to escape fromannular spaces 85 surrounding the holding bolts 5 within the aforesaidbosses I5 and I 5A in the valve cover 2 through which the bolts pass.Each of the air vent valves is urged by a spring 86 onto its seat, whichlatter is formed at the bottom of a hollow valve body 81 screwed intothe top of the hand knob I on the holding bolt 5. The valve body isprovided with ports 88 communicating with atmosphere, and the saidannular space 85 around the holding bolt 5 communicates with the hollowspace 89 in the hand knob 1 below the valve 84 through a lateral port 90and an axial passage 9| formed at the top end of the holding bolt. Thevalve stem 92 projects out of the valve body and thus provides a pressbutton by which the valve may be opened. I

The filter A is isolated from the system by pulling the handle end 53Aof the control valve lever 53 in the direction of filter A against thestop 68 on that side of the valve cover. In these circumstances, theinlet port 30 in the valve face 25, which communicates through thepassage 33 in'the valve plate 3 with the port I! in the carrier leadingto filter A is masked by the blank or unperiorated sector to of thecontrol valve It,

which lies between the two inlet ports 4| and 42 in the latter. The mainoil inlet chamber 2| in the valve cover is, therefore, cut of! from theinlet which was previously masked by the blank or' unperforated sector40 of the control valve, now registers with the corresponding port 42 inthe valve. Oil can then flow from the oil inlet chamber 2| in the valvecover 2 through the port 42, port 3| in the valve plate, passage 34 inthe latter into the inlet to the filter B in the carrier I. Further, thetransfer passage 44 in the control valve I9, which, by spanning the mainoutlet port 28 and the port 21 in the valve face, previously providedcommunication between the main outlet port 28 and the\ outlet port 21which communicates through the passage 35 in the valve plate with theoutlet I3 from filter A in the carrier I, is now moved so that, byspanning the main outlet port 28 and the outlet port 29 in the valveface, it provides communication between the said main outlet port 28 andthe port 29 in the valve face communicating through the passage 36 inthe valve plate with the outlet I3, from the filter B in the carrier I.At the same time the blank segment 45 of the valve is moved into aposition where it masks the outlet port 21 in the valve face thuscutting ofi the flow of outlet oil from filter A out of the passage 35in the valve plate. In these circumstances, therefore, oil can pass asabove described through the inlet and outlet passages of filter B whichis thereby placed in operation, while on the other hand the inlet andoutlet passages of filter A being masked, the latter is isolated fromthe system and ceases to operate. When the control valve I9 is turned inthe direction indicated above, the lug 63 on the bolt plate 60 engagesin one of the recesses I2 in the flange I3 of the hand knob I attachedto the holding bolt 5 of the filter-B and thus prevents that filterbeing opened inadvertently.

The control valve has only two operative positions, namely, one in whichthe hand lever 53 abuts against the stop 68, Fig. 10, in which positionthe filter A is isolated from the system as described above, and theother in which the hand lever abuts against the stop 69, in whichposition the filter B is isolated from the system.

In the latter position, the inlet port 3I in the valve plate is maskedby the blank part 40 of the control valve so that oil cannot flow fromthe main oil inlet chamber 2I in the valve cover 2 through the inletport 3| in the valve plate and thence to the inlet of the filter Bthrough the port It in the carrier I. The port 4| in the control valve,however, registers with the port 30 in the valve face 26, so that oilfrom the main inlet chamber 2I in the valve cover can flow into theinlet to the filter A through the ports II, 30, passage 33 in the valveplate and the inlet port I I in the carrier I.

Further, as the transfer passage 43 in the control valve now spans themain outlet port 28 and the outlet port 21 in the valve face 26 oil canflow from the outlet from the filter A through the corresponding outletport I3 in the carrier, passage 35, port 21, transfer passage 44 andport 23, in the valve plate to the main outlet passage 23 in the valvecover through the passage 31 and outlet port 38 in the valve plate.

On the other hand, in this position of the convide communication betweenthe main outlet port 28 and the port 29, no oil from the outlet of thefilter B can flow out of the passage 35 in the valve plate, the port 29being masked by the blank part 46 of the valve.

While I have described and illustrated but one embodiment of myinvention, it will be appreciated that numerous variations thereof canbe made without departing from the spirit and scope of my invention,and, therefore, I desire to be lim-- 7 ited only by the appended claims.

I claim: 1

1. A duplex filter of the class described, comprising a multi-unitcommon head, a carrier forming one of said head units, two spacedseparate containers supported by said carrier, each container housing afilter element, said carrier being provided with spaced outlet portscommunicating with the filter element outlets and with spaced inletports communicating with the filter element inlets, a valve plateforming a second of said head units and superimposed upon said carrier,said valve plate being provided with spaced outlet ports each of whichcommunicates with one of said carrier outlet ports, said valve platebeing provided with a main outlet port isolated from said firstmentioned outlet ports and which communicates with an outlet passageformed in said valve plate, said valve plate being provided with spacedinlet ports each of which communicates with one of said carrier inletports, a valve cover forming a third of said head units and superimposedon said valve plate, said cover being formed with an inlet connectionand a main inlet chamber in communication therewith and with said valveplate inlet ports, said cover being .formed with an outlet passage incommunication with said valve plate outlet passage, and a control valveturnably mounted on said valve plate controlling the flow of liquidthrough said valve plate 'ports, said control valve being provided withspaced inlet ports separated by an unperforated sector in face-to-facecontact with said valve plate, said spacing being such that when one ofsaid control valve inlet ports registers with one of said valve plateinlet ports, the other valve plate inlet port is masked by saidunperforated sector,

.said control valve also being provided with a transfer passage inconstant communication with said main outlet port in the valve plate andwith one of said first mentioned valve plate outlet ports depending uponthe position of the control valve, the arrangement being such that theinlet and outlet of a single filter element are Operatively said head.each of said bolts being detachable from its associated container, asecuring knob threaded on each of said bolts and in contact with saidhead to draw the associated container against said head, said securingknob having a part forming a locking element, a main inlet formed insaid head, a main outlet formed in said head, valve means enclosedwithin said head and arranged to place the inlet and the outlet of oneof said filter elements into communication with said main inlet and saidmain outlet, respectively, means projecting from said head and connneced to said valve means to shift said valve means to place one or theother of said filter elements into operative condition, and a bolt plateassociated with said valve shifting means and adapted to engage saidlocking elements, said bolt plate being operated to engage the lockingelement for the container which encloses the filter element in operativecondition thereby preventing removal of this container, said bolt platebeing simultaneously disengaged from the locking element for the othercontainer thereby permitting removal of this latter container.

3. The combination set forth in claim 2, including means for releasingair entrapped in either filter element, said means comprising an airvent valve mounted in said securing knob, means proiecting from saidknob to open said vent valve, and a passage through said holding boltand said head to the interior of said filter element through which theentrapped air may pass. CAMILLE CLARE SPRANKLING LE CLAIR.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Germany Sept. 8, 193a

